Shared-Use Path Level of Service Calculator

A User's Guide

Research and Development
Turner-Fairbank Highway Research Center
U.S. Department of Transportation
6300 Georgetown PikeFederal Highway Administration
McLean, Virginia 22101-2296

Pedestrian and Bicycle Safety

FOREWORD

Shared-use paths are paved, off-road facilities designed for travel by a variety of nonmotorized users, including bicyclists, pedestrians, skaters, runners, and others. Shared-use path planners and designers face a serious challenge in determining how wide paths should be and whether the various modes of travel should be separated from each other. Currently, very little substantive guidance is available to aid in those decisions.

This document describes how to use a new method to analyze the quality of service provided by shared-use paths of various widths that accommodate various travel mode splits. Given a count or an estimate of the overall path user volume in the design hour, the new method described here can provide the level of service (LOS) for path widths ranging from 2.4 to 6.1 meters (8.0 to 20.0 feet). The document describes in detail the input data needed to begin using the method, provides step-by-step instructions, and provides example applications of the new method. This document also describes how to use a spreadsheet calculation tool called SUPLOS that was also developed as part of the same effort and that is being circulated by the Federal Highway Administration.

The information in this document should be of interest to planners, engineers, park and recreation professionals, and others involved in the planning, design, operation, and/or maintenance of shared-use paths. In addition, this document will be of interest to researchers investigating how to analyze multiple modes of travelers in a finite space with minimal traffic control.

Michael F. TrentacosteDirector, Office of SafetyResearch and Development

Notice

This document is disseminated under the sponsorship of the U.S. Department of Transportation in the interest of information exchange. The U.S. Government assumes no liability for the use of the information contained in this document.

The
U.S. Government does not endorse products or manufacturers. Trademarks or manufacturers' names appear in this report only because they are considered essential to the objective of the document.

Quality Assurance Statement

The Federal Highway Administration (FHWA) provides high-quality information to serve Government, industry, and the public in a manner that promotes public understanding. Standards and policies are used to ensure and maximize the quality, objectivity, utility, and integrity of its information. FHWA periodically reviews quality issues and adjusts its programs and processes to ensure continuous quality improvement.

Shared-use paths are becoming increasingly busy in many places in the United States. Path designers and operators need guidance on how wide to make new or
rebuilt paths and whether to separate the different types of users. The current guidance is not very specific, has not been calibrated to conditions in the
United States, and does not accommodate the range of modes found on a typical U.S. path. The purpose of this project was to develop a level of service (LOS)
estimation method for shared-use paths that overcomes these limitations. The research included the development of the theory of traffic flow on a path, an
extensive effort to collect data on path operations, and a survey during which path users expressed their degree of satisfaction with the paths shown on a
series of videos.

Based on the theory developed and the data collected, the researchers developed an LOS estimation method for bicyclists that requires minimal input and
produces a simple and useful result. The method requires only four inputs from the user: One-way user volume in the design hour, mode split percentages, trail
width, and presence or absence of a centerline. Factors involved in the estimation of an LOS for a path include the number of times a typical bicyclist meets or
passes another path user and the number of those passes that are delayed. The method considers five types of path users when calculating adult bicyclists' LOS,
including other adult bicyclists, child bicyclists, pedestrians, runners, and in-line skaters.

This report provides step-by-step instructions on how to use the LOS procedure and spreadsheet calculation tool, which can be downloaded from the
Turner-Fairbank Highway Research Center Web site at www.tfhrc.org. Other products of the effort include FHWA-HRT-05-137 Evaluation of Safety, Design, and
Operation of Shared-Use Paths: Final Report, which documents the research and the spreadsheet calculation tool and is the basis of FHWA-HRT-05-139
Evaluation of Safety, Design, and Operation of Shared-Use Paths TechBrief.